Folding machine



June 12, 1962 E. SEHL ETAL 3,038,390

FOLDING MACHINE Filed June 12, 1959 2 Sheets-Sheet 1 IA/VEh/TORS'. EUGENE SEHL,

WQLTEQ 0. TEBEAU, 5/ W 1 Patented June 12, I932 lice 3,038,390 FOLDING MACHINE Eugene Sehl and Walter D. Tebeau, St. Louis, Mo., as-

signors to Western Supplies Company, St. Louis, Mo., a corporation of Missouri Filed June 12, 1959, Ser. No. 819,963 9 Claims. (Cl. 93-51) The present invention relates to a material folding apparatus of the type adapted to fold the edges of one piece of material about a smaller piece of material which has been glued to the first one.

The principal object of the present invention is to pro vide a folding apparatus which is easy to use and inexpensive to manufacture, but yet which is positive in operation. The apparatus includes a block of rubber or the like, mounted upon an ejector plate. The rubber block includes a recess cut to conform to the external shape of the finished folded product.

A creasing block has an external shape and configuration which is similar to but slightly smaller than the recess cut into the rubber block. When the material to be folded (which is of somewhat larger size than the rubber recess) is placed on top of the rubber recess with its edges extending at equal distances beyond the perimeter of the recess, the creasing block is applied to the top of the material to force it into the cavity within the rubber recess. The action of the creasing block will cause the edges of the material to be creased and folded along the sides of the rubber recess.

A pressing block of somewhat larger size than the rubber recess is provided for placement between the creasing block and the rubber block. When the material has been urged into the rubber cavity and creased by the creasing block, the pressing plate is next placed over the rubber cavity and then forced downwardly, compressing the rubber, and therewith urging the edges of the material over into a semi-folded condition.

The final step to the folding operation is formed by the creasing block which passes into the rubber recess and presses the already semi-folded edges of the material down against the central portions of the material. Inasmuch as glue will have been applied to the edges, they will be retained in the folded position.

Pin means extendable through the bottom of the recess are provided for rejecting the folded material.

Another important object of the present invention is to provide a positively acting folding device which requires a minimum number of mechanical par-ts and which is extremely simple to operate.

Further objects will be apparent from the more detailed description of the invention.

In the drawings:

FIGURE 1 is a top plan view of the creasing block assembly;

FIGURE 2 is an elevational view of the creasing block assembly;

FIGURE 3 is a bottom plan view of the creasing block assembly of FIGURE 1;

FIGURE 4 is a view in section of the creasing block assembly taken along the lines 44 of FIGURE 1;

FIGURE 5 is a top plan view of the pressing plate;

FIGURE 6 is a side elevation of the pressing plate;

FIGURE 7 is a top plan view of the mold assembly;

FIGURE 8 is a view in section taken along the lines 8-8 of FIGURE 7;

FIGURE 9 is a view in section taken along the lines 9-9 of FIGURE 7;

FIGURE 10 is a top plan view of the material to be folded before it is placed in the folding apparatus;

FIGURE 11 is a partial view in section similar to that of FIGURE 9 showing the material placed in the mold and ready for the beginning of an operation;

FIGURE 12 is a view similar to FIGURE 11 showing the creasing block applying a crease to the material;

FIGURE 13 is a view in section taken along the lines 13-43 of FIGURE 12;

FIGURE 14 is a view similar to that of FIGURE 12 but showing the pressing block in readiness for a pressing operation;

FIGURE 15 is a view in section taken along the lines IS-15 of FIGURE 14;

FIGURE 16 is a view similar to FIGURE 15 but with the pressing block shown pressing the material into a semi-folded condition;

FIGURE 17 is a view in section similar to FIGURE 14 showing the creasing block applying the final fold to the material;

FIGURE 18 is a view in section taken along the lines 18-18 of FIGURE 17;

FIGURE 19 is a view in section similar-to that of FIG- URE 18 showing the ejector pins ejecting the folded material from the mold;

FIGURE 20 is a plan view of the folded finished product; and

FIGURE 21 is a bottom view of the folded finished product.

Referring to the drawings, a die 30 includes a thin base plate 31 for stabilizing the structure which is mounted upon it. The base plate 31 includes holes 32 by which it may be mounted to a work table or other supporting means.

A rectangular supporting block 33 is secured to the mounting plate 31 by bolts 34. The mounting plate 31 will have tapped holes 35 to receive the bolts 34.

Spaced from the upper surface 36 of the supporting block 33 are a pair of rectangular horizontally disposed recesses 37 and 38. The recesses 37 and 38 open to the front surface 39 and the bottom surface 40 of the supporting block 33. The inner ends 41 and 42 of the recesses 37 and 38, respectively, are located far enough within the interior of the supporting blocks 33 that the ejector pins can be positioned beneath the die recess as will be described hereafter.

Each of the recesses 37 and 38 has a vertical hole 43 and 44, respectively, extending through the upper surface 36 of the supporting block 33. The holes '43 and 44 are so located that they will open beneath the die recess.

The ejector assembly comprises a U-shaped operating handle 59 having two arms 51 and 52. Each of the arms 51 and 52 is bent near its middle 53 so a to define a pair of levers 54 which will be horizontally disposed while the arms 51 and 52 extend at an angle to the mounting plate 31. The bent portions 53 will serve as fulcrum points whereby the depression of the handle will cause the assembly to pivot about the fulcrums 53 and the levers 54 to be raised.

A pair of shafts 55 are threaded at 56 into the mounting plate 31. The levers 54 each have holes 57 through which the shafts 55 pass. The shafts 55 each have enlarged heads 58 so that a compression coil spring 59 can be placed between each head 58 and its corresponding lever 54 to hold the levers downwardly against. the supporting plate 31.

At the inner ends 60 of the levers 54 a pair of dowel pins 61 are riveted at 62 in a loose fit so that there will be some pivotal movement of the dowel pins 61 about the ends 60 of the levers 54. The dowel pins 61 are of such a length that when the levers 54 are horizontally disposed against the mounting plate 31, the upper end of the dowel pins 61 will be flush with the upper surface 36 of the supporting block 33, It will be appreciated that as the handle 50 is depressed, the levers 54 will cause the dowel pins 61 to be raised into the die recess to be presently described. The compression springs 59 will return the levers 54 when the handle 56 is released.

The die assembly comprises a rubber block or pad 65 glued to a thin plate or sheet 66. Both the rubber pad 65 and the plate 66 to which it is glued have a die recess 67 through them. The recess 67 is of an articulate shape clearly illustrated in FIGURE 7, and is of the same size and shape as the folded finished product. It will be appreciated that for different shaped finished products, the hole 67 will be shaped correspondingly differently. As can be seen from FIGURE 7, the recess 61 is positioned directly over the dowel pins 61.

A retainer plate 78 extends over most of the rubber pad 65 but has one end 71 terminated short of the end of the recess 6'7. A recess 72 cut into the retainer plate is clearly indicated at FIGURE 7 to be somewhat larger and of a different shape than the recess 67 through the rubber pad 65. The recess 72 corresponds to the shape of the largest unfolded piece of material which is to be placed into the machine. The size and shape of the recess 72 will be governed by the configuration of the material to be folded The retainer plate 70 and the rubber pad 65 with its plate 66 are all secured to the supporting block 33. This securernent may be by screws or by a plurality of rivets 73. Obviously, the connection together of the retainer plate 79, the rubber pad '65, the plate 66 and the supporting block 33 will take place before the resulting assembly is secured to the mounting plate 31.

A creasing block assembly 80' is provided for applying both the initial crease to the material and the final fold. A plate 81 has locking pins 82 riveted to it so as to extend from its upper surface. The locking pins 82 serve as a means of attachment to a conventional machine of the type adapted to reciprocate the pressing block assembly 80 in a vertical direction. Such a machine will thus serve as a power source for forcing the creasing block assembly 80 down into the resilient recess 67. A locating pin 83 is also attached to the upper surface of the plate 81.

The creasing block 85 which is part of the assembly 80 is illustrated as including two sections 86 and 87. Both sections have the shape illustrated in FIGURE 3. This is the same shape as the recess 67, but is uniformly smaller than that recess so that the block 87 can freely pass within the recess 67. The lower surface 88 of the block 87 has recesses 89 and 90. The purpose of the recesses 89 and 90 is to define a border 91 about the perimeter of the block 87. The border 91 causes the folding force applied by the creasing block assembly 80 to be concentrated around the edges of the material. In the embodiment illustrated it is contemplated that one end of the material will not be folded. Accordingly, an end 92 of the block 87 does not include the border 91. The blocks 86 and 87 are secured to the plate 81 by bolts 93 threaded into tapped holes in the blocks 86 and 87. The bolts 93 terminate short of the bottom surface 88 of the block 87 so that they will not interfere with the configuration of the bottom surface 88.

A pressing plate 100 includes a flat plate 101 of the same shape as the recess 72 in the retainer plate 70. The rear end 102 of the pressing plate 1610 will extend beyond the retainer plate 70. That end 102 is shaped and sized to correspond to the adjacent end of the rubber pad 65 so that it will pass within the recess 67 at that end. This arrangement is provided since the embodiment illustrated does not contemplate the folding over of one end of the material, A wooden handle 103 is attached to the pressing plate 101 by a slightly curved shaft 104. The shaft 104 is curved to raise the handle 103 slightly for ease of grasping and to assure that the handle 103 will not interfere with the folding operation.

The material to be folded is illustrated in FIGURE as comprised of two pieces. The larger piece 110 has its edges 111 coated with glue. Spaced slits 112 are prod vided along the edge 111 to afford a smooth fold of angular surfaces. One end 113 of the material 110 has the glue omitted since that end is not to be folded.

The smaller piece 114 is glued to the larger piece 110. The smaller piece is of the size and shape of the finished product, being slightly smaller than the recess 67 through the rubber pad 65. The larger piece is of the same size and shape as the recess 72 through the retainer plate 70.

The pieces of material are placed upon the die 30 with the smaller piece 114 facing upwardly. It will be appreciated that the recess 72 serves to position the material over the recess 67 Operation To begin a folding operation, the material will be placed over the recess 67 within the recess 72 as aforesaid. The ejector handle 50 will have been released so that the dowel pins 61 reside within the lower extremes of the recesses 37 and 38. The operation comprises essentially four main steps, the creasing step, the semi-folding step, the final folding step, and the ejecting step.

With the material placed over the recess 67, the creasing step is performed by the creasing block assembly 80. That assembly is lowered toward the material as illustrated in FIGURE 11. The creasing block assembly is pressed downwardly forcing the material into the recess 67, as illustrated in FIGURE 12. Since the edges 111 of the larger piece 110 of material extend beyond the edges of the recess 67, they will be folded upwardly as the block 87 forces the material into the recess 67. The edges of the creasing block concentrating pressure upon the edges of material, a slight crease will be formed at the folding lines.

When the creasing bloc-k assembly 80 is raised out of the recess 67, the frictional engagement of the edges 111 with the rubber pad 65 will cause the material to remain with the recess 67 against the upper surface 36 of the supporting block 33.

The pressing plate is used to partially fold over the material which has been forced into the recess 67. As can be seen from FIGURES 14 and 15, the recess is smaller than the pressing plate 100 so that it will not freely pass within the recess. Nevertheless, the pressing plate 100 is forced down toward the material at the bottom of the recess 67. This is accomplished by lowering the creasing block 87 down against the upper surface of the pressing plate 101.

Further forcing of the pressing plate 101 downwardly by the creasing block 87 squashes the resilient pad 65, causing it to deform in the manner illustrated in FIGURE 16. Since the pad 65 is compressed in a vertical direction, it tends to expand horizontally thereby causing the vertical surfaces of the recess to converge toward the center of the recess 67. As the sides of the recess 67 so converge, they force the edges 111 of the piece of material to fold inwardly.

Since the edges of the creasing block caused the downward force of that block during the first step to concentrate the pressure against the edges of the material 1 10, a crease was caused to form in that material. Consequently, after the pressing plate 101 is raised out of the recess 67, the edges 111 of the material 110 will remain folded over to some extent. Since it is only necessary that the edges 111 be folded beyond a vertical position, the fold caused by the deformation of the recess 67 will be sufficient to condition the material for the final folding step.

To finally fold the material, the creasing block 87 is again brought down into the recess after the pressing plate 101 has been removed. The block 87 first engages the partially folded edges 111 of the material 110 and, as the block 87 moves downwardly, it forces the edges 11 1 to completely fold over against the body of the smaller piece of material 114. The glue previously applied to the edges 111 will cause those edges to adhere to the material 114 after the block 87 is removed from the recess.

After the creasing block is removed, the material is readily ejected from the recess by depression of the handle 50 connected to the operating levers 54. As those levers 54 pivot, they force the ejector pin 61 upwardly through the holes 43 to push the material out of the recess.

FIGURES 20 and 21 illustrate the form of the finished folded product as illustrated in the present embodiment.

Various changes and modifications may be made within the process of this invention as will be readily apparent to those skilled in the art. Such changes and modifications are within the scope and teaching of this invention as defined by the claims appended hereto.

What is claimed is:

1. A method of folding the edges of material comprising the steps of placing the material over a resilient pad having a recess in it of the size and shape of the finished product, but smaller than the size of the unfolded material; forcing the material into the recess so that the edges of the material will be turned up against the sides of the recess; squashing the resilient pad so that the sides of the recess will turn in, and with them the edges of the material will turn in; and thereafter pressing the edges against the body of the material.

2. Material folding apparatus comprising a resilient block mounted upon a rigid base; a recess through the resilient block of a smaller transverse area than the size of the material to be folded; the recess having substantially the same shape as the shape of the material after it is folded; means for forcing the material to the bottom of the recess against the base; means for squashing the resilient block against the base so as to cause the sides of the recess to converge toward the center of the recess, and with them the edges of the material; and means to flatten the edges against the body of the material.

3. The apparatus of claim 2 wherein the means for forcing the material into the recess comprises a creasing block assembly including a block of the same shape as, but smaller than, the recess for passing Within the recess and carrying the material with it to the bottom of the recess.

4. The apparatus of claim 2 wherein the means for squashing the resilient block comprises a pressing plate of somewhat larger size than the recess for compressing the resilient block adjacent the rim of the recess toward the base and wherein the resilient block is mounted between the rigid base and a guide plate, the guide plate having a slot for positioning the pressing plate.

5. The apparatus of claim 2 including means through the base for ejecting the folded product.

6. The apparatus of claim 5 wherein the ejecting means comprises a pair of levers pivotally mounted in horizontally spaced relationship to the resilient recess; a passage through the base for each lever; a hole connecting each passage with the resilient recess; said levers each including an ejector pin mounted to the end of the lever within the passage and projecting through a hole for movement into the resilient recess when the levers are pivoted.

7. The method of folding the edges of a piece of flexible material comprising the steps of placing the material over a recess in a resilient pad with the edges to be folded resting upon the pad beyond the rim of the recess, forcing the body of the material to the bottom of the recess with the edges to be folded turned up against the side walls of the recess, squashing the pad so that the side walls of the recess are turned inwardly far enough to establish an acute angle between the edges of the material and the body of the material that is against the bottom of the recess, relieving the pad so that it can return to its unsquashed condition while the edges remain at an acute angle relative to the body of the material, and thereafter pressing the edges fiat against the body of the material.

8. The method of claim 7 wherein the side walls of the recess are substantially planar and normal to the bottom of the recess and the bottom of the recess is substantially planar.

9. Apparatus for folding the edges of a piece of material back upon the body of the material comprising a resilient pad mounted upon a rigid base, a recess in the pad and opening through the side of the pad opposite the rigid base, the recess having side walls that are substantially normal to the base, a rigid creasing block having side walls that are spaced inwardly from the side walls of the recess by approximately the thickness of the material to be folded, means for passing the creasing block into the recess, and a pressing plate of somewhat larger size than the recess opening for squashing the pad to reduce the size of the recess opening.

References Cited in the file of this patent UNITED STATES PATENTS 1,348,369 Morrison Aug. 3, 1920 2,232,729 Randolph Feb. 25, 1941 2,394,219 Vachon Feb. 5, 1946 2,568,698 Amberg Sept. 25, 1951 2,749,867 Engel June 12, 1956 2,954,725 Palmer Oct. 4, 1960 

